Chat*- IV. ROMAN. 179

present day, the aqueduct and railroad might be taken as a fair test of their ability ; to elfeetthe one is as difficult as the other, and the same kind of talent is required in both ; he whocould perform the one might safely be entrusted with the other. It this opinion is correct,we ought not to be satisfied that during the last two thousand years we have made suf-ficient progress, and the historian may, perhaps, be induced to say we had not yet arrivedat the excellence attained in former times. When the writer visited this splendid Romanwork in the year 1817, it was about to receive a considerable repair: no monument ismore deserving of being upheld than the Pont du Gard ; it is an evidence of the talent andskill of the Roman engineers in their best days, and worthy of being studied by all whohave the conducting of water to a great and important city.

Aqueduct of Volsci, an ancient city of Etruria , the date of which is not accurately ascer-tained, though its manner of construction indicates the period of the empire, of which it isa splendid specimen.

Fig. 206.

aqueduct near volsci.

Modern writers wonder why aqueducts were built in preference to the humble and ordinarymethod of conveyance of water in pipes, and condemn Sextus V., Nicholas Vand PaulV., who during their sovereignty as Popes used similar means to bring three noble streamsof water into Rome . In the first place, any metal pipes laid across the Campagna or marshyland in the neighbourhood of that city, would not only have perished ultimately from theabundance of carbonic acid contained in the waters of the soil, but this dissolving the leador iron would poison all the inhabitants: in the next, the pipes would have been more costlythan masses of masonry, if the bore was sufficient to conduct the quantities which the archedaqueducts were enabled to do. By taking the levels accurately at first, and allowing theproper fall throughout, a regular supply was maintained, and the water, perfectly purethroughout its whole course, was delivered into castelli, or reservoirs at a height above thelevel of the city which rendered any mechanical power unnecessary for its elevation : itcould from them be distributed to the baths, fountains, and private houses, by simplyopening the sluices at particular hours appointed for the purpose. The ancient aqueductsfor nearly 2000 years have conveyed running streams constantly, and if an estimate wasmade of the cost of their first construction in stone or brick, after the Roman manner,and another upon our system of pipes, their wear and tear, with the daily and hourlyexpense of steam-engine-power to raise the water, the balance would be found greatly infavour of the ancient method. The purity of the water and its abundance, which couldkeep hundreds of fountains of the imperial city, and still does, constantly playing, is anotherreason in their favour.

Aqueduct at Lyons. Augustus, Tiberius, and Claudius , all contributed to the embellishmentof this ancient town, then called Lugdunum. A palace erected by the latter emperor in the

Fig. 207.

AQUEDUCT AT LYONS.

highest part of the city requiring to be supplied with water, an aqueduct was constructedwith arches built of rubble stone, faced with opus rctieulatum. The manner in which this

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